Performance assessment of an integrated power generation and refrigeration system on hypersonic vehicles

Hypersonic vehicle as next generation aircraft/spacecraft has broad applications, but its power supply and refrigeration are strictly limited by finite cold source. In this article, an integrated power generation and refrigeration system is developed, in which low-temperature fuel is utilized as cold source and high-temperature fuel is used as heat source. A novel combined generator based on closed-Brayton-cycle (CBC) and thermoelectric generator (TEG) is proposed to enhance electric power through extending the available temperature range of cold source. The integrated system model which consists of a refrigerator, a simple recuperated CBC and a three-stage TEG, is established to assess performance. Results indicate that the combined CBC-TEG generator has great potential in electric power enhancement. The power has an increase of 18.2% compared with single CBC. Power increase percentage of combined generator reduces with fuel outlet temperature in primary cooler. Moreover, decoupling the cooling and heating process of the combined generator is beneficial for the matching between its cold source and heat source. This research provides an innovative technical solution for the power generation and refrigeration on hypersonic vehicles under finite cold source conditions.